By Kate Baggaley Stem cells can help heal long-term brain damage suffered by rats blasted with radiation, researchers report in the Feb. 5 Cell Stem Cell. The treatment allows the brain to rebuild the insulation on its nerve cells so they can start carrying messages again. The researchers directed human stem cells to become a type of brain cell that is destroyed by radiation, a common cancer treatment, then grafted the cells into the brains of irradiated rats. Within a few months, the rats’ performance on learning and memory tests improved. “This technique, translated to humans, could be a major step forward for the treatment of radiation-induced brain … injury,” says Jonathan Glass, a neurologist at Emory University in Atlanta. Steve Goldman, a neurologist at the University of Rochester in New York, agrees that the treatment could repair a lot of the damage caused by radiation. “Radiation therapy … is very effective, but the problem is patients end up with severe disability,” he says. “Fuzzy thinking, a loss in higher intellectual functions, decreases in memory — all those are part and parcel of radiation therapy to the brain.” For children, the damage can be profound. “Those kids have really significant detriments in their adult IQs,” Goldman says. Radiation obliterates cells that mature into oligodendrocytes, a type of cell that coats the message-carrying part of nerve cells with insulation. Without that cover, known as the myelin sheath, nerve cells can’t transmit information, leading to memory and other brain problems. © Society for Science & the Public 2000 - 2015

Keyword: Learning & Memory; Glia
Link ID: 20563 - Posted: 02.07.2015

By Gary Stix Everyone knows that ALS is a very bad disease, an awareness underscored by the recent Ice Bucket Challenge. The death of neurons that results in paralysis can be caused by specific genetic mutations. But in most cases, single genes are not the culprit. So researchers have looked for other risk factors that might play a role. Studies have tagged cigarette smoking as a definite danger. Alcohol, another plausible suspect, has yielded equivocal results in previous investigations. To get a better read on ethanol (some earlier studies were small), researchers from Sweden’s Lund University looked at giant medical registries from that country, compiled at various times between 1973 and 2010. They found that individuals who were classified as problem drinkers were a little more than half as likely to be diagnosed with ALS as those who didn’t have “alcohol use disorder.” More than 420,000 problem drinkers were registered during the period surveyed—and there were 7965 patients who received an ALS diagnosis. The study, just reported in The European Journal of Neurology, controlled for gender, education and place of birth, among other factors. But it was unable to tell why drinking might help. It did lead, though, to a number of intriguing speculations. The researchers cited studies in rats, done by other groups, that indicated that ingestion of alcohol decreased the number of brain cells called astrocytes that bore high levels of a certain protein linked to the pathology of ALS. © 2015 Scientific American

Keyword: ALS-Lou Gehrig's Disease ; Glia
Link ID: 20562 - Posted: 02.07.2015

By Nick Lavars Keeping ourselves upright is something most of us shouldn't need to think a whole lot about, given we've been doing it almost our entire lives. But when it comes to dealing with more precarious terrain, like walking on ice or some sort of tight rope, you might think some pretty significant concentration is required. But researchers have found that even in our moments of great instability, our subconsciousness is largely responsible for keeping us from landing on our backsides. This is due to what scientists are describing as a mini-brain, a newly mapped bunch of neurons in the spinal cord which processes sensory information and could lead to new treatment for ailing motor skills and balance. "How the brain creates a sensory percept and turns it into an action is one of the central questions in neuroscience," says Martin Goulding, senior author of the research paper and professor at the Salk Institute. "Our work is offering a really robust view of neural pathways and processes that underlie the control of movement and how the body senses its environment. We’re at the beginning of a real sea change in the field, which is tremendously exciting.” The work of Goulding and his team focuses on how the body processes light touch, in particular the sensors in our feet that detect changes in the surface underfoot and trigger a reaction from the body. "Our study opens what was essentially a black box, as up until now we didn’t know how these signals are encoded or processed in the spinal cord," says Goulding. "Moreover, it was unclear how this touch information was merged with other sensory information to control movement and posture."

Keyword: Movement Disorders
Link ID: 20561 - Posted: 02.07.2015

by Andy Coghlan Apple's the word. Chimpanzees can learn to grunt "apple" in two chimp languages – a finding that questions how unique our own language abilities are. Researchers have kept records of vocalisations of a group of adult chimps from the Netherlands before and after the move to Edinburgh zoo. Three years later, recordings show, the Dutch chimps had picked up the pronunciation of their Scottish hosts. The finding challenges the prevailing theory that chimp words for objects are fixed because they result from excited, involuntary outbursts. Humans can easily learn foreign words that refer to a specific object, and it was assumed that chimps and other animals could not, perhaps owing to their different brain structure. This has long been argued to be one of the talents making humans unique. The assumption has been that animals do not have control over the sounds they make, whereas we socially learn the labels for things – which is what separates us from animals, says Katie Slocombe of the University of York, UK. But this may be wrong, it seems. "The important thing we've now shown is that with the food calls, they changed the structure to fit in with their new group members, so the Dutch calls for 'apple' changed to the Edinburgh ones," says Slocombe. "It's the first time call structure has been dissociated from emotional outbursts." © Copyright Reed Business Information Ltd.

Keyword: Language; Evolution
Link ID: 20560 - Posted: 02.07.2015

By Anne Harding NEW YORK (Reuters Health) - Reduced sexual activity could cause a dip in testosterone levels in older men, new findings suggest. Among men 70 and older, those who reported a decline in sexual activity and desire over a two-year period also showed small declines in serum testosterone, Dr. David Handelsman of the ANZAC Research Institute at the University of Sydney and Concord Hospital in New South Wales, Australia, and colleagues found. They report their findings in the Journal of Clinical Endocrinology and Metabolism, online January 28. "Decline in serum testosterone is more likely to be the result rather than the cause of sexual dysfunction among older men who don't have reproductive disorders," Dr. Handelsman told Reuters Health by email. "The widely prevalent misinterpretation of this (as if the mild lowering of serum testosterone needs or might benefit from testosterone treatment) is one of the main drivers of the massive over-use of testosterone prescriptions in North America over the last decade." While declines in androgens and sexual function are both thought to be aging-related, Dr. Handelsman and his colleagues note in their report, the relationship between androgen levels and sexual function is not clear. To better understand the temporal and predictive relationship between androgen levels and sexual function, the researchers looked at 1,226 men participating in the Concord Health and Ageing in Men Project (CHAMP), measuring their levels of testosterone, dihydrotestosterone, estradiol, and estrone with liquid chromatography-tandem mass spectrometry. Men also reported on their sexual function using standardized questions, at baseline and two years later. © 2015 Scientific American

Keyword: Sexual Behavior; Hormones & Behavior
Link ID: 20559 - Posted: 02.07.2015

by Sandrine Ceurstemont Malte Andersson from the University of Gothenburg in Sweden has been testing whether Norwegian lemmings (Lemmus lemmus), like the one in the video above, deter predators by warning them of their aggressive nature with their shrieks. The vivid markings on the fur also indicate to predators that this critter isn't for eating. Having such warning colours – a phenomenon known as aposematism – is common in insects, snakes and frogs, but unusual in herbivorous mammals. This combination of hues made the lemmings easier to spot than their plain-looking neighbours, grey-sided voles. When a predator, played by humans in Andersson's test, is far away, these lemmings prefer to go unnoticed, he found. But when predators get closer, to within a few metres, these lemmings were much more likely to give out a warning call than their browner relatives. The conspicuous colours, aggressive calls and threatening postures together let predators know to expect a fight, and potentially damage, if they attempt to eat a Norwegian lemming. In contrast with the voles, these lemmings aggressively resist attacks by predatory birds. © Copyright Reed Business Information Ltd.

Keyword: Aggression
Link ID: 20558 - Posted: 02.07.2015

By Nicholas Weiler When you spend your days battling giant squid, it’s good to have friends you can rely on. New research from the Caribbean suggests that female sperm whales (Physeter macrocephalus, pictured) swim with favored companions and form long-term family allegiances. Sperm whales raise their young in communal family groups of about a dozen related females, but mapping out the giant animals' social lives in much detail has been a challenge for scientists. The whales spend 60% of their lives hunting squid hundreds of meters below the waves, and researchers can watch them interact for only a few minutes at a time when they surface to breathe. But a new multiyear study has created the most detailed map yet of sperm whales’ social networks. Between 2005 and 2010, scientists followed nine whale families along the west coast of the Caribbean island of Dominica and mapped their social relationships by counting which females spent the most time together at the surface between dives. As expected, whales mostly preferred to relax with family members, but within families they played favorites, frequently swimming with the same sister, auntie, or aged granny, the researchers report online this week in Animal Behaviour. The network diagram also revealed three pairs of families that mingled frequently over the years to socialize and share babysitting duty. One of these pairs has been fraternizing since 1995, according to data from other researchers, suggesting that such allegiances can last more than a decade. These observations suggest sperm whale families may be similar to the matriarchal clans of elephants, which also form long-lasting family bonds, the researchers say. Further research may determine whether allied families are actually distant cousins and investigate whether whales use signature songs to find their best friends. © 2015 American Association for the Advancement of Science

Keyword: Sexual Behavior; Aggression
Link ID: 20557 - Posted: 02.07.2015

By Angelina Fanous After the height of the Ice Bucket Challenge last fall, I found myself at a dinner party where the conversation turned to A.L.S. — amyotrophic lateral sclerosis — the disease for which millions were dousing themselves to raise awareness and money. “Would you rather have A.L.S., Alzheimer’s, or Parkinson’s?” someone asked. All those diseases are devastating, but A.L.S. is unique in that it usually kills within two to three years of diagnosis. It was just a game to my friends, all of whom are in their 20s. Everyone chose A.L.S., agreeing that it would be the fastest and therefore easiest death. But I stayed silent. I hadn’t yet told my friends that I had been diagnosed with A.L.S. in July — two months after my 29th birthday. Had I been healthy, I might have answered A.L.S., too. But since my diagnosis, all I have wanted is more time. When I first noticed I couldn’t type with my left hand, the doctors narrowed down it down to two options: a treatable autoimmune disease or A.L.S. They initially began treating me for the autoimmune disease. About once a month, we shut down my immune system so it would stop attacking my central nervous system. But with no immune system I made regular visits to the E.R. “At least it’s not A.L.S.,” I consoled myself. When the treatment didn’t work and the weakness spread to my left leg and right hand, A.L.S. was the only remaining possibility. Still, I did that socially acceptable but also borderline insane thing where I sought second, third and fourth opinions. I voluntarily subjected myself to excruciating medical tests. I got shocked with electricity, had my spinal fluid drained, and underwent a surgery to remove a piece of my muscles and nerves, all in the hopes of finding a different diagnosis. All of the tests confirmed the diagnosis of A.L.S. © 2015 The New York Times Company

Keyword: ALS-Lou Gehrig's Disease
Link ID: 20556 - Posted: 02.05.2015

Alison Abbott Fabienne never found out why she went into labour three months too early. But on a quiet afternoon in June 2007, she was hit by accelerating contractions and was rushed to the nearest hospital in rural Switzerland, near Lausanne. When her son, Hugo, was born at 26 weeks of gestation rather than the typical 40, he weighed just 950 grams and was immediately placed in intensive care. Three days later, doctors told Fabienne that ultrasound pictures of Hugo's brain indicated that he had had a severe haemorrhage from his immature blood vessels. “I just exploded into tears,” she says. Both she and her husband understood that the prognosis for Hugo was grim: he had a very high risk of cerebral palsy, a neurological condition that can lead to a life of severe disability. The couple agreed that they did not want to subject their child to that. “We immediately told the doctors that we did not want fierce medical intervention to keep him alive — and saw the relief on the doctors' faces,” recalls Fabienne, who requested that her surname not be used. That night was the most tortured of her life. The next day, however, before any change had been made to Hugo's treatment, his doctors proposed a new option to confirm the diagnosis: a brain scan using magnetic resonance imaging (MRI). This technique, which had been newly adapted for premature babies, would allow the doctors to predict the risk of cerebral palsy more accurately than with ultrasound alone, which has a high false-positive rate. Hugo's MRI scan showed that the damage caused by the brain haemorrhage was limited, and his risk of severe cerebral palsy was likely to be relatively low. So just 24 hours after their decision to let his life end, Hugo's parents did an about-turn. They agreed that the doctors should try to save him. © 2015 Nature Publishing Group

Keyword: Development of the Brain
Link ID: 20555 - Posted: 02.05.2015

By Amanda Baker While we all may vary on just how much time we like spending with other people, humans are overall very social beings. Scientists have already found this to be reflected in our health and well-being – with social isolation being associated with more depression, worse health, and a shorter life. Looking even deeper, they find evidence of our social nature reflected in the very structure of our brains. Just thinking through your daily interactions with your friends or siblings probably gives you dozens of examples of times when it was important to interpret or predict the feelings and behaviors of other people. Our brains agree. Over time parts of our brains have been developed specifically for those tasks, but apparently not all social interaction was created equally. When researchers study the brains of people trying to predict the thoughts and feelings of others, they can actually see a difference in the brain activity depending on whether that person is trying to understand a friend versus a stranger. Even at the level of blood flowing through your brain, you treat people you know well differently than people you don’t. These social interactions also extend into another important area of the brain: the nucleus accumbens. This structure is key in the reward system of the brain, with activity being associated with things that leave you feeling good. Curious if this could have a direct connection with behavior, one group of scientists studied a very current part of our behavior as modern social beings: Facebook use. © 2015 Scientific American

Keyword: Development of the Brain
Link ID: 20554 - Posted: 02.05.2015

By ALAN SCHWARZ High numbers of students are beginning college having felt depressed and overwhelmed during the previous year, according to an annual survey released on Thursday, reinforcing some experts’ concern about the emotional health of college freshmen. The survey of more than 150,000 students nationwide, “The American Freshman: National Norms Fall 2014,” found that 9.5 percent of respondents had frequently “felt depressed” during the past year, a significant rise over the 6.1 percent reported five years ago. Those who “felt overwhelmed” by schoolwork and other commitments rose to 34.6 percent from 27.1 percent. Conducted by the Cooperative Institutional Research Program at the University of California, Los Angeles’s Higher Education Research Institute for almost 50 years, the survey assesses hundreds of matters ranging from political views to exercise habits. It is considered one of the most comprehensive snapshots of trends among recent high school seniors and is of particular interest to people involved in mental well-being. “It’s a public health issue,” said Dr. Anthony L. Rostain, a psychiatrist and co-chairman of a University of Pennsylvania task force on students’ emotional health. “We’re expecting more of students: There’s a sense of having to compete in a global economy, and they think they have to be on top of their game all the time. It’s no wonder they feel overwhelmed.” Other survey results indicated that students were spending more time on academics and socializing less — trends that would normally be lauded. But the lead author of the study, Kevin Eagan, cautioned that the shift could result in higher levels of stress. © 2015 The New York Times Company

Keyword: Depression; Development of the Brain
Link ID: 20553 - Posted: 02.05.2015

|By Andrea Anderson and Victoria Stern Blood type may affect brain function as we age, according to a new large, long-term study. People with the rare AB blood type, present in less than 10 percent of the population, have a higher than usual risk of cognitive problems as they age. University of Vermont hematologist Mary Cushman and her colleagues used data from a national study called REGARDS, which has been following 30,239 African-American and Caucasian individuals older than 45 since 2007. The aim of the study is to understand the heavy stroke toll seen in the southeastern U.S., particularly among African-Americans. Cushman's team focused on information collected twice yearly via phone surveys that evaluate cognitive skills such as learning, short-term memory and executive function. The researchers zeroed in on 495 individuals who showed significant declines on at least two of the three phone survey tests. When they compared that cognitively declining group with 587 participants whose mental muster remained robust, researchers found that impairment in thinking was roughly 82 percent more likely in individuals with AB blood type than in those with A, B or O blood types, even after taking their race, sex and geography into account. The finding was published online last September in Neurology. The seemingly surprising result has some precedent: past studies suggest non-O blood types are linked to elevated incidence of heart disease, stroke and blood clots—vascular conditions that could affect brain function. Yet these cardiovascular consequences are believed to be linked to the way non-O blood types coagulate, which did not seem to contribute to the cognitive effects described in the new study. The researchers speculate that other blood-group differences, such as how likely cells are to stick to one another or to blood vessel walls, might affect brain function. © 2015 Scientific American

Keyword: Alzheimers
Link ID: 20552 - Posted: 02.05.2015

By Monique Brouillette When the first four-legged creatures emerged from the sea roughly 375 million years ago, the transition was anything but smooth. Not only did they have to adjust to the stress of gravity and the dry environment, but they also had to wait another 100 million years to evolve a fully functional ear. But two new studies show that these creatures weren’t deaf; instead, they may have used their lungs to help them hear. Fish hear easily underwater, as sound travels in a wave of vibration that freely passes into their inner ears. If you put a fish in air, however, the difference in the density of the air and tissue is so great that sound waves will mostly be reflected. The modern ear adapted by channeling sound waves onto an elastic membrane (the eardrum), causing it to vibrate. But without this adaptation, how did the first land animals hear? To answer this question, a team of Danish researchers looked at one of the closest living relatives of early land animals, the African lungfish (Protopterus annectens). As its name suggests, the lungfish is equipped with a pair of air-breathing lungs. But like the first animals to walk on land, it lacks a middle ear. The researchers wanted to determine if the fish could sense sound pressure waves underwater, so they filled a long metal tube with water and placed a loudspeaker at one end. They played sounds into the tube in a range of frequencies and carefully positioned the lungfish in areas of the tube where the sound pressure was high. Monitoring the brain stem and auditory nerve activity in the lungfish, the researchers were surprised to discover that the fish could detect pressure waves in frequencies above 200 Hz. © 2015 American Association for the Advancement of Science

Keyword: Hearing; Evolution
Link ID: 20551 - Posted: 02.05.2015

by Jacob Aron Ever struggled to tell the difference between two shades of paint? When it comes to colour, one person's peach is another's puce, but there are 11 basic colours that we all agree on. Now it seems two more should be in the mix: lilac and turquoise. In 1969, two researchers looked at 100 languages and found that all had words for black, white, red, green, yellow, blue, brown, purple, pink, orange and grey. These terms pass a number of tests: they refer to easily distinguishable colours, are widely used and are single words. The chart divided into basic colours (Image: D.Mylonas/L.MacDonald) We might quibble over which shade is cream or peach, for example, but everyone knows yellow when they see it. There are exceptions - Russian and Greek speakers have separate words for light and dark blue. Now Dimitris Mylonas of Queen Mary University of London and Lindsay MacDonald of University College London says the same applies to two more colours, in the case of English-speakers, at least. For the past seven years, they've been running an online test in which people name a range of shades – you can try it for yourself. Results from 330 participants were analysed to pick out basic names. These were ranked in a number of ways, such as how often each colour name came up and whether the name was unique to one shade or common to many. Lilac and turquoise came ninth and tenth overall, beating white, red and orange. The only measure turquoise didn't score highly on was the time it took people to enter an answer, says Mylonas. "Our observers had problems spelling it correctly." © Copyright Reed Business Information Ltd.

Keyword: Vision
Link ID: 20550 - Posted: 02.05.2015

by Bethany Brookshire The windup before the pitch. The take-away before the golf swing. When you learn to pitch a softball, swing a golf club or shoot a basketball, you learn that preparation is important. You also learn about follow-through — the upswing of the golf club or the bend in the elbow after a softball pitch. It’s the preparation and the execution that get the ball across the plate, so why should we care about follow-through? In theory, once the ball has left your hands or sailed away from your club or racket, there’s no movement you could make that could affect what happens next. So while some follow-through might be important to diffuse the energy you just put into your shot, it shouldn’t really matter whether you swing your golf club up in an arc, whip it off to the side or club your opponent over the head with it. But follow-through is in fact quite important, and not just as an extension of the movements that preceded it. Consistent follow-through actually helps performance, reports neuroscientist Ian Howard and colleagues at the University of Plymouth in England. The finding gives coaches some science to back up their training, and helps scientists understand how the brain accesses motor memories. Howard has always been interested in how the brain learns movement tasks. “The first study we did looked at the preparation movement — you move backwards and then you move forwards [as in a golf swing],” he says. His lab found that the preparation before a particular motion had a strong effect on how our brains learn and recall motor movements. © Society for Science & the Public 2000 - 2015.

Keyword: Movement Disorders
Link ID: 20549 - Posted: 02.05.2015

By Maria Konnikova R. T. first heard about the Challenger explosion as she and her roommate sat watching television in their Emory University dorm room. A news flash came across the screen, shocking them both. R. T., visibly upset, raced upstairs to tell another friend the news. Then she called her parents. Two and a half years after the event, she remembered it as if it were yesterday: the TV, the terrible news, the call home. She could say with absolute certainty that that’s precisely how it happened. Except, it turns out, none of what she remembered was accurate. R. T. was a student in a class taught by Ulric Neisser, a cognitive psychologist who had begun studying memory in the seventies. Early in his career, Neisser became fascinated by the concept of flashbulb memories—the times when a shocking, emotional event seems to leave a particularly vivid imprint on the mind. William James had described such impressions, in 1890, as “so exciting emotionally as almost to leave a scar upon the cerebral tissues.” The day following the explosion of the Challenger, in January, 1986, Neisser, then a professor of cognitive psychology at Emory, and his assistant, Nicole Harsch, handed out a questionnaire about the event to the hundred and six students in their ten o’clock psychology 101 class, “Personality Development.” Where were the students when they heard the news? Whom were they with? What were they doing? The professor and his assistant carefully filed the responses away. In the fall of 1988, two and a half years later, the questionnaire was given a second time to the same students. It was then that R. T. recalled, with absolute confidence, her dorm-room experience. But when Neisser and Harsch compared the two sets of answers, they found barely any similarities.

Keyword: Learning & Memory
Link ID: 20548 - Posted: 02.05.2015

By Virginia Morell To prevent their hives from being attacked by invaders, wasps must quickly distinguish friend from foe. They typically do this by sniffing out foreigners, as outsiders tend to have a different scent than the home colony. Now researchers have discovered that, like a few other wasp species, a tiny social wasp (Liostenogaster flavolineata) from Malaysia employs an additional security measure: facial recognition. The wasps’ nests are typically found in large aggregations with as many as 150 built close together, and each colony faces persistent landing attempts by outsiders from these other nests. To find out why and how these wasps employ both vision and scent to determine if an incoming wasp is a comrade, scientists carried out a series of experiments on 50 colonies (see photo above) in the wild. Close to the nests, the researchers dangled lures made of captured and killed wasps. The lures had been given different treatments. For instance, some lures made from nest mates were coated with a foe’s scent, whereas outsiders were painted with the colony’s odor. The wasps, it turns out, pay more attention to facial markings than to scent when faced with a possible intruder, the team reports online today in the Proceedings of the Royal Society B. Indeed, in tests where the wasps could assess both an intruder’s face and scent, they relied solely on facial recognition and immediately attacked those whose faces they didn’t know, ignoring their odor. That’s the safest strategy, the scientists note, because the wasps can recognize another’s face at a distance, but need to actually touch another wasp to detect her scent—not a bad ploy for a tiny-brained insect. © 2015 American Association for the Advancement of Science

Keyword: Attention
Link ID: 20547 - Posted: 02.05.2015

By Pam Belluck A large new study has documented unexpected links in the timing and severity of symptoms of maternal depression, which could help mothers and doctors better anticipate and treat the condition. The study of more than 8,200 women from 19 centers in seven countries, published last month in Lancet Psychiatry, found that in those with the severest symptoms — suicidal thoughts, panic, frequent crying — depression most often began during pregnancy, not after giving birth, as is often assumed. Moderately depressed women often developed their symptoms postpartum, and were more likely than severely depressed women to have experienced complications during pregnancy like pre-eclampsia, gestational diabetes or hypertension. Severely depressed women, however, more often reported complications during delivery. “This is the largest study to date on postpartum depressive symptoms,” said Leah Rubin, an assistant professor in the Women’s Mental Health Research Program at University of Illinois at Chicago, a co-author of a commentary about the study. “This is definitely a first step in the right direction, knowing that depression isn’t one-size-fits-all.” Ten to 20 percent of mothers experience depression, anxiety, bipolar disorder or other symptoms at some point from pregnancy to a year after giving birth. The study could aid efforts to find causes and treatments. The study participants were all mothers. Some had been found to have postpartum depression by clinicians, while others were assessed via a widely used questionnaire. (Some participants fell into both groups.) © 2015 The New York Times Company

Keyword: Depression
Link ID: 20546 - Posted: 02.03.2015

by Penny Sarchet It's a familiar sight: a flock of birds flying overhead in a classic V-formation, each saving energy by stealing lift from the bird flying ahead. But what's in it for the bird out front? For northern bald ibises, it's all about taking turns. The leading bird soon swaps places with the bird immediately behind it, in a rare example of a phenomenon called reciprocal altruism. To understand how birds cooperate in flight, Bernhard Voelkl at the University of Oxford and his team tagged every ibis in a group of 14 with high-precision GPS data loggers, allowing them to measure each individual's position in relation to the rest of the flock. They found that individual birds changed positions frequently, and were only in an aerodynamically helpful position about a third of the time. Most of these formations comprised just two birds sharing duties equally. "For whichever combination of two birds we looked at, we saw that the time bird A was flying in front of bird B matched closely the time bird B was flying in front of bird A," says Voelkl. And this wasn't just an average over the 39 kilometres that the flock flew – Voelkl's team frequently observed swaps within a pair happening within seconds, with the leader moving back behind the same bird for a similarly timed spell of following. "This immediacy of the reciprocation reduces the opportunity for cheating," says Voelkl. "Direct swaps also mean that you do not have to memorise who is 'owing' you leading time, so doesn't require a lot of memory." © Copyright Reed Business Information Ltd.

Keyword: Emotions
Link ID: 20545 - Posted: 02.03.2015

By Katherine Ellison Dr. Mark Bertin is no A.D.H.D. pill-pusher. The Pleasantville, N.Y., developmental pediatrician won’t allow drug marketers in his office, and says he doesn’t always prescribe medication for children diagnosed with attention deficit hyperactivity disorder. Yet Dr. Bertin has recently changed the way he talks about medication, offering parents a powerful argument. Recent research, he says, suggests the pills may “normalize” the child’s brain over time, rewiring neural connections so that a child would feel more focused and in control, long after the last pill was taken. “There might be quite a profound neurological benefit,” he said in an interview. A growing number of doctors who treat the estimated 6.4 million American children diagnosed with A.D.H.D. are hearing that stimulant medications not only help treat the disorder but may actually be good for their patients’ brains. In an interview last spring with Psych Congress Network, http://www.psychcongress.com/video/are-A.D.H.D.-medications-neurotoxic-or-neuroprotective-16223an Internet news site for mental health professionals, Dr. Timothy Wilens, chief of child and adolescent psychiatry at Massachusetts General Hospital, said “we have enough data to say they’re actually neuroprotective.” The pills, he said, help “normalize” the function and structure of brains in children with A.D.H.D., so that, “over years, they turn out to look more like non-A.D.H.D. kids.” Medication is already by far the most common treatment for A.D.H.D., with roughly 4 million American children taking the pills — mostly stimulants, such as amphetamines and methylphenidate. Yet the decision can be anguishing for parents who worry about both short-term and long-term side effects. If the pills can truly produce long-lasting benefits, more parents might be encouraged to start their children on these medications early and continue them for longer. Leading A.D.H.D. experts, however, warn the jury is still out. © 2015 The New York Times Company

Keyword: ADHD; Development of the Brain
Link ID: 20544 - Posted: 02.03.2015